Coating Arrangement

ABSTRACT

A coating arrangement has the following characteristics: -particles having a scratch hardness greater than or equal to 9 and a median grain size that can be determined, -a coating having a thickness equaling approximately half the median grain size, -a coating carrier with a surface comprising recesses, wherein a portion greater than 85% of the recesses compared to a surface surrounding the associated recess is designed with a depth smaller than approximately 10% and/or a opening width smaller than or equal to approximately 15% of the coating thickness, and -the coating is applied to the surface of the coating carrier and surrounds the particles at least at a lower region oriented toward the coating carrier.

The invention relates to a coating arrangement.

An entire array of friction-increasing coatings are known from the prior art, the coefficients of adhesive friction thus achievable still being in need of improvement for many applications, however.

An object of the invention is therefore to provide an improved coating arrangement, using which high coefficients of adhesive friction are achievable in particular.

The object is achieved by the subject matter of claim 1. Advantageous embodiments are described in the subclaims.

As claimed in claim 1, a coating arrangement comprises the following features:

-   -   particles having a Mohs hardness greater than or equal to 9 and         a predefinable mean grain size,     -   a coating having a thickness approximately corresponding to half         of the mean grain size,     -   a coating carrier having a surface comprising depressions, a         proportion greater than 85% of the depressions being implemented         having a depth less than approximately 10% and/or an opening         width less than or equal to approximately 15% of the coating         thickness in relation to a surface environment surrounding the         particular depression, and     -   the coating is applied to the surface of the coating carrier and         encloses the particles at least in a lower area oriented toward         the coating carrier.

In particular in that the surface of the coating carrier is implemented by grinding, for example, in such a manner that the furrowed depressions are implemented having a depth less than approximately 10% and/or an opening width less than approximately 15% of the coating thickness in relation to a surface environment surrounding the particular depression, optimum adhesion is ensured for the coating and the particles are simultaneously prevented from more or less disappearing into depressions in such a manner that they do not contribute to increasing the friction of the coating arrangement.

In an advantageous embodiment, the coating is implemented as electroplated nickel, so that an excellent protective layer against environmental influences which cause corrosion and other environmental influences is generated simultaneously for the coating carrier.

In an advantageous embodiment, the coating carrier is implemented as having a greater Mohs hardness and/or a greater tensile strength as a counter element, against which the coating arrangement is provided to be pressed against, so that if desired the areas of the particles protruding beyond the coating are pressed into the counter element and the coating below the particles and the area of the coating carrier below the particles are only slightly deformed in relation to the pressing into the counter element.

Further advantages, features, and details of the invention result from the exemplary embodiment of the invention described hereafter on the basis of the figures. In the figures:

FIG. 1 shows a perforated-disk-like component on which a coating is applied and

FIG. 2 shows a fundamental structure of the coating from FIG. 1.

FIG. 1 shows a perforated-disk-like component which is provided with a coating as an exemplary embodiment of the invention. The perforated-disk-like component is divided into a plurality of sector-like subelements 50, each of the subelements 50 comprising three holes 52. The perforated-disk-like component is provided for use in the area of a shaft coupling, the perforated-disk-like component being situated, for example, between flange-like widened shaft ends of two shaft elements to be connected to one another, such as a main shaft of a deep-sea wind power plant. The two flanges of the two shaft elements are also implemented having corresponding passages or pocket holes corresponding to the holes 52 of the perforated-disk-like component, so that the two flange-like shaft ends can be screwed together through the holes 52, having the perforated-disk-like component situated between them. In one embodiment, coding, such as teeth, can be implemented on the periphery of the perforated-disk-like component, so that it is possible to detect a shaft speed in this manner.

In order that the two flange-like shaft ends are connected to one another as fixedly as possible, the perforated-disk-like component is implemented at least on its two front sides having a coating in the context of a coating arrangement. A schematic diagram of the coating arrangement is shown in FIG. 2. The perforated-disk-like component comprises a coating carrier 10, which is implemented from a steel having a tensile strength between approximately 600 and 800 MPa and has a Mohs hardness of 6, the steel type Domex 500 MC being able to be used, for example. The frontal surfaces of the coating carrier 10 are implemented as ground in such a manner that the surface has a roughness of R_(a)≦0.2 μm and the furrowed depressions 12 caused by the grinding are implemented having a depth less than or equal to 4 μm and an opening width less than or equal to 6 μm in relation to a surface environment surrounding the particular depression 12.

A lower coating 22 made of nickel having a thickness of approximately 5 μm is then applied by electroplating to the coating carrier 10 ground in this manner. Particles 30 having a Mohs hardness of 10 and a mean grain size of approximately 120 μm, in particular round or blocky grain of a monocrystalline diamond, such as a natural diamond, are then laid on this lower coating 22. An upper coating 24 made of nickel is subsequently also applied thereon by electroplating, so that the particles 30 laid on the lower coating 22 are enclosed by the upper coating 24 at least in a lower area oriented toward the coating carrier 10. The upper coating 24 is applied up to a thickness of approximately 55 μm, so that the total thickness of the coating corresponds to approximately half of the mean grain size.

According to the preceding description, both front sides of the coating carrier 10 are accordingly implemented as coated. The two flange-like shaft ends of the two shaft elements are implemented from a material which has lesser values than the coating carrier 10 both in regard to Mohs hardness and also tensile strength, the shaft ends being implemented in particular from gray cast iron, such as GG 40.3 having a tensile strength in the range between 400 and 500 MPa and a Mohs hardness of 5. The flange faces provided for application to the perforated-disk-like component are implemented having a roughness R_(a) in the range between 0.5 and 1.5 μm.

If the two shaft ends are fixedly screwed together having the perforated-disk-like component situated between them, the diamond particles 30 are pressed into the gray cast iron when the screw connection is formed so that the perforated-disk-like component is connected in an interlocking manner to the shaft ends. Only a slight compression of the lower coating 22 situated below the particular diamond grain 30 and the coating carrier areas situated underneath occurs in the direction of the perforated-disk-like component when the parts are screwed together. Coefficients of friction greater than 0.8 can particularly advantageously be implemented as described above. Furthermore, the nickel coating simultaneously represents an excellent corrosion protection for the coating carrier 10 made of steel, so that the perforated-disk-like component is securely protected even against the most unfavorable weathering conditions.

For example, a number of screws may further advantageously be reduced upon use of the above-described coating in relation to conventional connections, with the same strength of the connection. 

1. A coating arrangement, comprising: a plurality of particles, each particle having a Mohs hardness a coating carrier having a surface and plurality of depressions formed in the surface, and a coating applied to the surface of the coating carrier so as to enclose the particles and having a thickness of about half of the particle mean grain size, wherein at least 85% of the depressions being formed such that each depression has at least one of a depth of less than about 10% of the coating thickness and an opening width of up to about 15% of the coating thickness in relation to a surface environment surrounding the particular depression.
 2. The coating arrangement as claimed in claim 1, wherein greater than 99% of the depressions are formed such that each depression has at least one of a depth of less than about 10% of the coating thickness and an opening width of up to about 15% of the coating thickness in relation to a surface environment surrounding the particular depression.
 3. The coating arrangement as claimed in claim 1, wherein the depressions are formed such that each depression has a depth of up to 6 μm.
 4. The coating arrangement as claimed in claim 1, wherein the depressions are formed such that each depression has an opening width of less than about 8 μm.
 5. The coating arrangement as claimed in one claim 1, wherein the surface of the coating carrier is formed having a roughness Ra of up to 0.2 μm.
 6. The coating arrangement as claimed in claim 1, wherein the coating carrier is formed having a Mohs hardness of at least
 5. 7. The coating arrangement as claimed in claim 1, wherein the coating carrier is formed of a steel having a tensile strength within a range of about 600 MPa and about 800 MPa.
 8. The coating arrangement as claimed in claim 1, wherein the surface of the coating carrier is formed by grinding.
 9. The coating arrangement as claimed in claim 1, wherein the coating has a thickness with a range of about 45 μm and about 75 μm.
 10. The coating arrangement as claimed in claim 1, wherein the coating, includes a lower coating applied to the surface of the coating carrier, the lower coating having a thickness of less than about 10% of the a total thickness of the coating and the particles being disposed on the lower coating, and an upper coating applied to the lower coating.
 11. The coating arrangement as claimed in claim 10, wherein the lower coating is formed having a thickness of about 5 μm.
 12. The coating arrangement as claimed in claim 10, wherein at least one of the lower coating and the upper coating includes nickel.
 13. The coating arrangement as claimed in claim 10, wherein at least one of the lower coating and the upper coating is applied by electroplating.
 14. The coating arrangement as claimed in claim 13, wherein the lower coating and the upper coating are formed of a same material.
 15. The coating arrangement as claimed in claim 1, wherein each of the particles have a Mohs hardness of
 10. 16. The coating arrangement as claimed in claim 1, wherein the particles include a monocrystalline diamond.
 17. The coating arrangement as claimed in claim 1, further comprising a counter element having a Mohs hardness of about 5, the coating being pressed against the counter element.
 18. The coating arrangement as claimed in claim 1, further comprising a counter element, formed of gray cast iron having a tensile strength within a range of about 400 MPa and about 500 MPa, the coating being pressed against the counter element.
 19. The coating arrangement as claimed in claim 1, further comprising a counter element having at least one of a hardness less than a hardness of the coating carrier and a tensile strength less than that a tensile strength of the coating carrier, the coating being pressed against the counter element.
 20. The coating arrangement as claimed in claim 1, wherein the coating arrangement is applied to at least one side of a perforated-disk-like component.
 21. The coating arrangement as claimed in claim 20, wherein the component is divided into a plurality of sector-like subelements.
 22. The coating arrangement as claimed in claim 20, wherein the component is includes a plurality of axial passages for receiving fasteners.
 23. The coating arrangement as claimed in claim 20, wherein the component is configured for use in a rigid shaft coupling.
 24. The coating arrangement as claimed in claim 20, wherein the component is has coding on a periphery of the component and adapted for acquiring a shaft speed.
 25. The coating arrangement as claimed in claim 24, wherein the coding includes teeth. 